Purpose:
Find the differences in structure of carbohydrates and how that translates to their characteristics.
Materials:
Petri-dishes(60 x 15 mm, sterile)
Tap water Fructose Lactose |
Plastic spoons
Sucrose Galactose Cellulose |
Paper cups
Glucose Maltose Starch |
Structural Formulas:
Procedure:
Part I
Find images of the structure of these eight carbohydrates: Sucrose, Glucose (Dextrose), Fructose, Galactose, Maltose, Lactose, Starch (Soluble), and Cellulose.
Part II
Taste a portion of each carbohydrate and rank them on a scale of 0-200 using Sucrose as a base of 100.
Properties of Carbohydrates:
Carbohydrate:
Sucrose Glucose (Dextrose) Fructose Galactose Maltose Lactose Starch (Soluble) Cellulose |
Type:
Disaccharide Monosaccharide Monosaccharide Monosaccharide Disaccharide Disaccharide Polysaccharide Polysaccharide |
Sweetness (0-200):
100 70 180 25 40 60 0 0 |
Color:
White, clear White Clear White White White White White/Yellow |
Texture:
Grainy, sugary Smooth, Grainy Crystal, Hard Powdery, Smooth Powdery Powdery (Choke) Dry Powdery Dry Powdery |
Function(s):
Energy, Transport Energy Energy Energy energy Energy Fuel for Energy Structure |
Data Analysis:
1. The sweetest carbohydrates were monosaccharide. The trend of sweetness suggested that the less number of rings, the sweeter the carbohydrate and vice-versa.
2. Similarly to sweetness the less rings in a carbohydrate, the less powdery the substance becomes and the more rings, the more crystalline and hard.
3. Most of us agreed on sweetness, but possible reasons for disagreement include different levels of sugar tolerance, cross-contamination between carbohydrates, and different ways of tasting.
4. As seen in Glucose and Galactose, the structurally-similar monosaccharides are similar in their sweetness.
2. Similarly to sweetness the less rings in a carbohydrate, the less powdery the substance becomes and the more rings, the more crystalline and hard.
3. Most of us agreed on sweetness, but possible reasons for disagreement include different levels of sugar tolerance, cross-contamination between carbohydrates, and different ways of tasting.
4. As seen in Glucose and Galactose, the structurally-similar monosaccharides are similar in their sweetness.
Reflection:
My favorite experiences in this lab were the surprised looks on faces after tasting some carbohydrates and tasting the sweetness of some carbohydrates.
As a group, my team of three worked efficiently and effectively. We each tasted every carbohydrate, asked for opinions and discussed, as well as tried to maintain a good working environment. We were not pressed for time or even worried about inaccurate test results. I thought this project was a great way to solidify groups while still learning.
If we did this project again, I would change very little. The only thing I can think of was possibly keeping cellulose shot consumption lower. Overall I found this lab a nice easy, but still intriguing way of looking at carbohydrates.
As a group, my team of three worked efficiently and effectively. We each tasted every carbohydrate, asked for opinions and discussed, as well as tried to maintain a good working environment. We were not pressed for time or even worried about inaccurate test results. I thought this project was a great way to solidify groups while still learning.
If we did this project again, I would change very little. The only thing I can think of was possibly keeping cellulose shot consumption lower. Overall I found this lab a nice easy, but still intriguing way of looking at carbohydrates.